QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
QUARTERLY FINANCIAL DATA (UNAUDITED)
Interest income	$ 13,832	$ 13,707	$ 13,677	$ 13,298	$ 13,026	$ 13,471	$ 12,333	$ 11,596	$ 54,514	$ 50,426	$ 44,899
Interest expense	1,896	1,889	1,872	1,898	1,983	1,949	1,872	1,812	7,555	7,616	7,740
Net interest income	11,936	11,818	11,805	11,400	11,043	11,522	10,461	9,784	46,959	42,810	37,159
Provision for loan losses	1,075	600	2,500	825	850	1,450	900	700	5,000	3,900	3,500
Net interest income after provision for loan losses	10,861	11,218	9,305	10,575	10,193	10,072	9,561	9,084	41,959	38,910	33,659
Non interest income	2,685	2,235	3,800	1,953	1,904	1,766	1,825	1,454	10,673	6,949	7,433
Non interest expenses	8,513	8,479	8,567	8,221	7,821	7,824	7,784	7,408	33,780	30,837	27,879
Income before income taxes	5,033	4,974	4,538	4,307	4,276	4,014	3,602	3,130	18,852	15,022	13,213
Income tax expense	1,623	1,614	1,475	1,368	1,326	1,241	1,126	970	6,080	4,663	4,047
Net income	$ 3,410	$ 3,360	$ 3,063	$ 2,939	$ 2,950	$ 2,773	$ 2,476	$ 2,160	$ 12,772	$ 10,359	$ 9,166
Basic earnings per share (in dollars per share)	$ 0.39	$ 0.39	$ 0.36	$ 0.35	$ 0.42	$ 0.41	$ 0.38	$ 0.34	$ 1.48	$ 1.54	$ 1.45
Diluted earnings per share (in dollars per share)	$ 0.39	$ 0.39	$ 0.36	$ 0.35	$ 0.42	$ 0.41	$ 0.38	$ 0.34	$ 1.48	$ 1.54	$ 1.45